<!DOCTYPE html>
<html lang="en-US">
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width,initial-scale=1">
    <title>合并配置的设计与实现 | 知识库演示</title>
    <meta name="generator" content="VuePress 1.9.9">
    <link rel="icon" href="/vdoing-demo-repository/img/favicon.ico">
    <meta name="description" content="web前端技术博客,简洁至上,专注web前端学习与总结。JavaScript,js,ES6,TypeScript,vue,python,css3,html5,Node,git,github等技术文章。">
    <meta name="keywords" content="前端博客,个人技术博客,前端,前端开发,前端框架,web前端,前端面试题,技术文档,学习,面试,JavaScript,js,ES6,TypeScript,vue,python,css3,html5,Node,git,github,markdown">
    <meta name="theme-color" content="#11a8cd">
    
    <link rel="preload" href="/vdoing-demo-repository/assets/css/0.styles.bb913129.css" as="style"><link rel="preload" href="/vdoing-demo-repository/assets/js/app.52e6b5d0.js" as="script"><link rel="preload" href="/vdoing-demo-repository/assets/js/2.f10ddeba.js" as="script"><link rel="preload" href="/vdoing-demo-repository/assets/js/152.ca32ca39.js" as="script"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/10.82e086d6.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/100.2570dab9.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/101.b429c13f.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/102.0e9afba4.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/103.42e8d9d6.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/104.6ca089b8.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/105.f02335fc.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/106.2fe52c32.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/107.7650f18b.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/108.7d825011.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/109.42092f8e.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/11.49ec595f.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/110.8e6f8d5b.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/111.84bc1774.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/112.5da6cb16.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/113.2eb6714d.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/114.dbdf6a79.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/115.96dc61ac.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/116.2774e841.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/117.5a0ea935.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/118.72005b7a.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/119.77fd4a33.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/12.66e2368f.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/120.994b6190.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/121.794bec47.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/122.239044f6.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/123.d6247b89.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/124.357cddf4.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/125.b27c8c6b.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/126.2f09d5b4.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/127.5b5e7dcc.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/128.ca8342ed.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/129.62196c04.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/13.01d28bf6.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/130.ae36e0a1.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/131.63408c4f.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/132.7a1bc472.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/133.6f365b21.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/134.7dfd70a1.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/135.c110453c.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/136.dea9b77b.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/137.212998a2.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/138.cf96d5b3.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/139.34437df0.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/14.52e25550.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/140.b28a1de4.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/141.d117632d.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/142.743bfbfc.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/143.d6c926e2.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/144.86916e4e.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/145.a4658544.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/146.9f190393.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/147.b53beefe.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/148.d49c882d.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/149.b5c8b142.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/15.ff9c9117.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/150.ab4902b7.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/151.aa13cf1a.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/153.f3dc7a9e.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/154.2198d119.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/155.6cf21591.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/156.929b9e50.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/157.6d227e19.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/158.ad6e937f.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/159.d74c55e1.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/16.a59e9d0e.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/160.1e9abdb1.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/161.5343ce3e.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/162.214b3f61.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/163.918d2361.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/164.204cab40.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/165.884ba632.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/166.e3bc3126.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/167.b8103188.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/168.176b21b8.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/169.56e67ae6.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/17.73f27920.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/170.05fe9454.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/171.ac72af48.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/172.134bd8be.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/173.f7b83d9b.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/174.bc7aa46f.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/175.c654668c.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/176.33b09327.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/177.97d7e55f.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/178.ab02c611.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/179.0d88c6f5.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/18.39e882fe.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/180.1a2df1f3.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/181.533495f7.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/182.a4fc6807.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/183.e3a44f30.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/184.b731d331.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/185.e6eb67ad.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/186.c2493cb4.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/187.279befae.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/188.1de7c987.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/189.e748958a.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/19.ef7490a3.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/190.ad045bc8.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/191.c3131762.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/192.29ea4e7e.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/193.1e75aa14.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/194.f1150906.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/195.2a593c50.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/196.5aa5efe2.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/197.a328dc59.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/198.9db60424.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/199.d3b39a54.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/20.b5301937.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/200.a9dae555.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/21.2e9bd506.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/22.02e5e5a0.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/23.a00bf08d.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/24.dae9e7bf.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/25.3120ccd4.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/26.628f5a86.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/27.d4e86439.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/28.642a9f76.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/29.6c013ead.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/3.c3e96c9f.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/30.4e45e23b.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/31.9b0c4fcb.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/32.347f1a82.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/33.a17e9f72.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/34.ae475141.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/35.70d7eb87.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/36.0166a619.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/37.8d63783a.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/38.91c94a9e.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/39.edf5fef6.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/4.f05e47c1.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/40.f2dfda35.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/41.488faa5e.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/42.258fde58.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/43.c46a30da.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/44.cfac4a51.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/45.58439e5f.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/46.91d42cf4.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/47.39ec1b7a.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/48.900b1d2a.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/49.4db4a295.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/5.85821e9b.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/50.4a48e245.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/51.32253e74.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/52.f9692c89.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/53.f93fad53.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/54.cccf7ffb.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/55.7e4f324a.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/56.5d04b9d7.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/57.ed34f737.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/58.9e762eed.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/59.81cfbcc1.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/6.5f8d8bd6.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/60.76f14de8.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/61.a4d207e0.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/62.fce4471e.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/63.58fd2153.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/64.b3f081c8.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/65.dbde37b1.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/66.49bc7970.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/67.48b689d5.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/68.a3660c81.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/69.b4057547.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/7.4acc3e20.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/70.5f3717cf.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/71.d47ff342.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/72.eca3c6ef.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/73.71bbaeec.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/74.6fe6e554.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/75.4dbad835.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/76.6ec52a3f.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/77.9041350a.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/78.e0b3aa97.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/79.1dbdb52c.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/8.503d9748.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/80.568b41f1.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/81.9394cc64.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/82.e36a0a2e.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/83.fba15f4a.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/84.1a6a64b4.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/85.af0f0d14.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/86.aed3f80d.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/87.08c34bee.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/88.52b2750e.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/89.6d27f363.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/9.9691b37e.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/90.cccb0e61.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/91.6fb1e7f3.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/92.9e3d1d8a.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/93.25bb0c7b.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/94.0a896da5.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/95.41991c9b.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/96.1f4103d8.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/97.97ec058f.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/98.f40afd31.js"><link rel="prefetch" href="/vdoing-demo-repository/assets/js/99.ac67e72d.js">
    <link rel="stylesheet" href="/vdoing-demo-repository/assets/css/0.styles.bb913129.css">
  </head>
  <body class="theme-mode-light">
    <div id="app" data-server-rendered="true"><div class="theme-container sidebar-open have-rightmenu"><header class="navbar blur"><div title="目录" class="sidebar-button"><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" role="img" viewBox="0 0 448 512" class="icon"><path fill="currentColor" d="M436 124H12c-6.627 0-12-5.373-12-12V80c0-6.627 5.373-12 12-12h424c6.627 0 12 5.373 12 12v32c0 6.627-5.373 12-12 12zm0 160H12c-6.627 0-12-5.373-12-12v-32c0-6.627 5.373-12 12-12h424c6.627 0 12 5.373 12 12v32c0 6.627-5.373 12-12 12zm0 160H12c-6.627 0-12-5.373-12-12v-32c0-6.627 5.373-12 12-12h424c6.627 0 12 5.373 12 12v32c0 6.627-5.373 12-12 12z"></path></svg></div> <a href="/vdoing-demo-repository/" class="home-link router-link-active"><img src="/vdoing-demo-repository/img/EB-logo.png" alt="知识库演示" class="logo"> <span class="site-name can-hide">知识库演示</span></a> <div class="links"><div class="search-box"><input aria-label="Search" autocomplete="off" spellcheck="false" value=""> <!----></div> <nav class="nav-links can-hide"><div class="nav-item"><a href="/vdoing-demo-repository/" class="nav-link">首页</a></div><div class="nav-item"><div class="dropdown-wrapper"><button type="button" aria-label="Python" class="dropdown-title"><a href="/vdoing-demo-repository/python/" class="link-title">Python</a> <span class="title" style="display:none;">Python</span> <span class="arrow right"></span></button> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><h4>Python</h4> <ul class="dropdown-subitem-wrapper"><li class="dropdown-subitem"><a href="/vdoing-demo-repository/pages/c438df/" class="nav-link">Python基础</a></li></ul></li></ul></div></div><div class="nav-item"><div class="dropdown-wrapper"><button type="button" aria-label="前端" class="dropdown-title"><a href="/vdoing-demo-repository/web/" class="link-title">前端</a> <span class="title" style="display:none;">前端</span> <span class="arrow right"></span></button> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><h4>前端文章</h4> <ul class="dropdown-subitem-wrapper"><li class="dropdown-subitem"><a href="/vdoing-demo-repository/pages/8143cc480faf9a11/" class="nav-link">JavaScript</a></li><li class="dropdown-subitem"><a href="/vdoing-demo-repository/pages/802a1ca6f7b71c59/" class="nav-link">Vue</a></li></ul></li><li class="dropdown-item"><h4>学习笔记</h4> <ul class="dropdown-subitem-wrapper"><li class="dropdown-subitem"><a href="/vdoing-demo-repository/note/javascript/" class="nav-link">《JavaScript教程》笔记</a></li><li class="dropdown-subitem"><a href="/vdoing-demo-repository/note/es6/" class="nav-link">《ES6 教程》笔记</a></li><li class="dropdown-subitem"><a href="/vdoing-demo-repository/note/vue/" class="nav-link">《Vue》笔记</a></li><li class="dropdown-subitem"><a href="/vdoing-demo-repository/note/typescript-axios/" class="nav-link">《TypeScript 从零实现 axios》</a></li><li class="dropdown-subitem"><a href="/vdoing-demo-repository/note/wx-miniprogram/" class="nav-link">小程序笔记</a></li></ul></li></ul></div></div><div class="nav-item"><div class="dropdown-wrapper"><button type="button" aria-label="页面" class="dropdown-title"><a href="/vdoing-demo-repository/ui/" class="link-title">页面</a> <span class="title" style="display:none;">页面</span> <span class="arrow right"></span></button> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="/vdoing-demo-repository/pages/8309a5b876fc95e3/" class="nav-link">HTML</a></li><li class="dropdown-item"><!----> <a href="/vdoing-demo-repository/pages/0a83b083bdf257cb/" class="nav-link">CSS</a></li></ul></div></div><div class="nav-item"><div class="dropdown-wrapper"><button type="button" aria-label="技术" class="dropdown-title"><a href="/vdoing-demo-repository/technology/" class="link-title">技术</a> <span class="title" style="display:none;">技术</span> <span class="arrow right"></span></button> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="/vdoing-demo-repository/pages/9a7ee40fc232253e/" class="nav-link">技术文档</a></li><li class="dropdown-item"><!----> <a href="/vdoing-demo-repository/pages/4c778760be26d8b3/" class="nav-link">GitHub技巧</a></li><li class="dropdown-item"><!----> <a href="/vdoing-demo-repository/pages/117708e0af7f0bd9/" class="nav-link">Nodejs</a></li><li class="dropdown-item"><!----> <a href="/vdoing-demo-repository/pages/41f87d890d0a02af/" class="nav-link">博客搭建</a></li></ul></div></div><div class="nav-item"><a href="/vdoing-demo-repository/archives/" class="nav-link">归档</a></div> <a href="https://github.com/xugaoyi/vuepress-theme-vdoing" target="_blank" rel="noopener noreferrer" class="repo-link">
    GitHub
    <span><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg> <span class="sr-only">(opens new window)</span></span></a></nav></div></header> <div class="sidebar-mask"></div> <div class="sidebar-hover-trigger"></div> <aside class="sidebar" style="display:none;"><!----> <nav class="nav-links"><div class="nav-item"><a href="/vdoing-demo-repository/" class="nav-link">首页</a></div><div class="nav-item"><div class="dropdown-wrapper"><button type="button" aria-label="Python" class="dropdown-title"><a href="/vdoing-demo-repository/python/" class="link-title">Python</a> <span class="title" style="display:none;">Python</span> <span class="arrow right"></span></button> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><h4>Python</h4> <ul class="dropdown-subitem-wrapper"><li class="dropdown-subitem"><a href="/vdoing-demo-repository/pages/c438df/" class="nav-link">Python基础</a></li></ul></li></ul></div></div><div class="nav-item"><div class="dropdown-wrapper"><button type="button" aria-label="前端" class="dropdown-title"><a href="/vdoing-demo-repository/web/" class="link-title">前端</a> <span class="title" style="display:none;">前端</span> <span class="arrow right"></span></button> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><h4>前端文章</h4> <ul class="dropdown-subitem-wrapper"><li class="dropdown-subitem"><a href="/vdoing-demo-repository/pages/8143cc480faf9a11/" class="nav-link">JavaScript</a></li><li class="dropdown-subitem"><a href="/vdoing-demo-repository/pages/802a1ca6f7b71c59/" class="nav-link">Vue</a></li></ul></li><li class="dropdown-item"><h4>学习笔记</h4> <ul class="dropdown-subitem-wrapper"><li class="dropdown-subitem"><a href="/vdoing-demo-repository/note/javascript/" class="nav-link">《JavaScript教程》笔记</a></li><li class="dropdown-subitem"><a href="/vdoing-demo-repository/note/es6/" class="nav-link">《ES6 教程》笔记</a></li><li class="dropdown-subitem"><a href="/vdoing-demo-repository/note/vue/" class="nav-link">《Vue》笔记</a></li><li class="dropdown-subitem"><a href="/vdoing-demo-repository/note/typescript-axios/" class="nav-link">《TypeScript 从零实现 axios》</a></li><li class="dropdown-subitem"><a href="/vdoing-demo-repository/note/wx-miniprogram/" class="nav-link">小程序笔记</a></li></ul></li></ul></div></div><div class="nav-item"><div class="dropdown-wrapper"><button type="button" aria-label="页面" class="dropdown-title"><a href="/vdoing-demo-repository/ui/" class="link-title">页面</a> <span class="title" style="display:none;">页面</span> <span class="arrow right"></span></button> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="/vdoing-demo-repository/pages/8309a5b876fc95e3/" class="nav-link">HTML</a></li><li class="dropdown-item"><!----> <a href="/vdoing-demo-repository/pages/0a83b083bdf257cb/" class="nav-link">CSS</a></li></ul></div></div><div class="nav-item"><div class="dropdown-wrapper"><button type="button" aria-label="技术" class="dropdown-title"><a href="/vdoing-demo-repository/technology/" class="link-title">技术</a> <span class="title" style="display:none;">技术</span> <span class="arrow right"></span></button> <ul class="nav-dropdown" style="display:none;"><li class="dropdown-item"><!----> <a href="/vdoing-demo-repository/pages/9a7ee40fc232253e/" class="nav-link">技术文档</a></li><li class="dropdown-item"><!----> <a href="/vdoing-demo-repository/pages/4c778760be26d8b3/" class="nav-link">GitHub技巧</a></li><li class="dropdown-item"><!----> <a href="/vdoing-demo-repository/pages/117708e0af7f0bd9/" class="nav-link">Nodejs</a></li><li class="dropdown-item"><!----> <a href="/vdoing-demo-repository/pages/41f87d890d0a02af/" class="nav-link">博客搭建</a></li></ul></div></div><div class="nav-item"><a href="/vdoing-demo-repository/archives/" class="nav-link">归档</a></div> <a href="https://github.com/xugaoyi/vuepress-theme-vdoing" target="_blank" rel="noopener noreferrer" class="repo-link">
    GitHub
    <span><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg> <span class="sr-only">(opens new window)</span></span></a></nav>  <ul class="sidebar-links"><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>初识 TypeScript</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>TypeScript 常用语法</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>ts-axios 项目初始化</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>ts-axios 基础功能实现</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>ts-axios 异常情况处理</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>ts-axios 接口扩展</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>ts-axios 拦截器实现</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading open"><span>ts-axios 配置化实现</span> <span class="arrow down"></span></p> <ul class="sidebar-links sidebar-group-items"><li><a href="/vdoing-demo-repository/pages/937e4de6b81edeca/" aria-current="page" class="active sidebar-link">合并配置的设计与实现</a><ul class="sidebar-sub-headers"><li class="sidebar-sub-header level2"><a href="/vdoing-demo-repository/pages/937e4de6b81edeca/#需求分析" class="sidebar-link">需求分析</a></li><li class="sidebar-sub-header level2"><a href="/vdoing-demo-repository/pages/937e4de6b81edeca/#默认配置" class="sidebar-link">默认配置</a><ul class="sidebar-sub-headers"><li class="sidebar-sub-header level3"><a href="/vdoing-demo-repository/pages/937e4de6b81edeca/#默认配置定义" class="sidebar-link">默认配置定义</a></li><li class="sidebar-sub-header level3"><a href="/vdoing-demo-repository/pages/937e4de6b81edeca/#添加到-axios-对象中" class="sidebar-link">添加到 axios 对象中</a></li></ul></li><li class="sidebar-sub-header level2"><a href="/vdoing-demo-repository/pages/937e4de6b81edeca/#配置合并及策略" class="sidebar-link">配置合并及策略</a><ul class="sidebar-sub-headers"><li class="sidebar-sub-header level3"><a href="/vdoing-demo-repository/pages/937e4de6b81edeca/#合并方法" class="sidebar-link">合并方法</a></li><li class="sidebar-sub-header level3"><a href="/vdoing-demo-repository/pages/937e4de6b81edeca/#默认合并策略" class="sidebar-link">默认合并策略</a></li><li class="sidebar-sub-header level3"><a href="/vdoing-demo-repository/pages/937e4de6b81edeca/#只接受自定义配置合并策略" class="sidebar-link">只接受自定义配置合并策略</a></li><li class="sidebar-sub-header level3"><a href="/vdoing-demo-repository/pages/937e4de6b81edeca/#复杂对象合并策略" class="sidebar-link">复杂对象合并策略</a></li></ul></li><li class="sidebar-sub-header level2"><a href="/vdoing-demo-repository/pages/937e4de6b81edeca/#flatten-headers" class="sidebar-link">flatten headers</a></li><li class="sidebar-sub-header level2"><a href="/vdoing-demo-repository/pages/937e4de6b81edeca/#demo-编写" class="sidebar-link">demo 编写</a></li></ul></li><li><a href="/vdoing-demo-repository/pages/f5b627bfebba87fc/" class="sidebar-link">请求和响应配置化</a></li><li><a href="/vdoing-demo-repository/pages/7b49658c26f613bf/" class="sidebar-link">扩展 create 静态接口</a></li></ul></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>ts-axios 取消功能实现</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>ts-axios 更多功能实现</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>ts-axios 单元测试</span> <span class="arrow right"></span></p> <!----></section></li><li><section class="sidebar-group collapsable depth-0"><p class="sidebar-heading"><span>ts-axios 部署与发布</span> <span class="arrow right"></span></p> <!----></section></li></ul> </aside> <div><main class="page"><div class="theme-vdoing-wrapper "><div class="articleInfo-wrap" data-v-06225672><div class="articleInfo" data-v-06225672><ul class="breadcrumbs" data-v-06225672><li data-v-06225672><a href="/vdoing-demo-repository/" title="首页" class="iconfont icon-home router-link-active" data-v-06225672></a></li> <li data-v-06225672><a href="/vdoing-demo-repository/note/typescript-axios/#《TypeScript 从零实现 axios》" data-v-06225672>《TypeScript 从零实现 axios》</a></li><li data-v-06225672><a href="/vdoing-demo-repository/note/typescript-axios/#ts-axios 配置化实现" data-v-06225672>ts-axios 配置化实现</a></li></ul> <div class="info" data-v-06225672><div title="作者" class="author iconfont icon-touxiang" data-v-06225672><a href="javascript:;" data-v-06225672>HuangYi</a></div> <div title="创建时间" class="date iconfont icon-riqi" data-v-06225672><a href="javascript:;" data-v-06225672>2020-01-05</a></div> <!----></div></div></div> <!----> <div class="content-wrapper"><div class="right-menu-wrapper"><div class="right-menu-margin"><div class="right-menu-title">目录</div> <div class="right-menu-content"></div></div></div> <h1><img src="">合并配置的设计与实现<!----></h1> <!----> <div class="theme-vdoing-content content__default"><h1 id="合并配置的设计与实现"><a href="#合并配置的设计与实现" class="header-anchor">#</a> 合并配置的设计与实现</h1> <h2 id="需求分析"><a href="#需求分析" class="header-anchor">#</a> 需求分析</h2> <p>在之前的章节我们了解到，在发送请求的时候可以传入一个配置，来决定请求的不同行为。我们也希望 <code>ts-axios</code> 可以有默认配置，定义一些默认的行为。这样在发送每个请求，用户传递的配置可以和默认配置做一层合并。</p> <p>和官网 <code>axios</code> 库保持一致，我们给 <code>axios</code> 对象添加一个 <code>defaults</code> 属性，表示默认配置，你甚至可以直接修改这些默认配置：</p> <div class="language-typescript line-numbers-mode"><pre class="language-typescript"><code>axios<span class="token punctuation">.</span>defaults<span class="token punctuation">.</span>headers<span class="token punctuation">.</span>common<span class="token punctuation">[</span><span class="token string">'test'</span><span class="token punctuation">]</span> <span class="token operator">=</span> <span class="token number">123</span>
axios<span class="token punctuation">.</span>defaults<span class="token punctuation">.</span>headers<span class="token punctuation">.</span>post<span class="token punctuation">[</span><span class="token string">'Content-Type'</span><span class="token punctuation">]</span> <span class="token operator">=</span> <span class="token string">'application/x-www-form-urlencoded'</span>
axios<span class="token punctuation">.</span>defaults<span class="token punctuation">.</span>timeout <span class="token operator">=</span> <span class="token number">2000</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br></div></div><p>其中对于 <code>headers</code> 的默认配置支持 <code>common</code> 和一些请求 <code>method</code> 字段，<code>common</code> 表示对于任何类型的请求都要添加该属性，而 <code>method</code> 表示只有该类型请求方法才会添加对应的属性。</p> <p>在上述例子中，我们会默认为所有请求的 <code>header</code> 添加 <code>test</code> 属性，会默认为 <code>post</code> 请求的 <code>header</code> 添加 <code>Content-Type</code> 属性。</p> <h2 id="默认配置"><a href="#默认配置" class="header-anchor">#</a> 默认配置</h2> <h3 id="默认配置定义"><a href="#默认配置定义" class="header-anchor">#</a> 默认配置定义</h3> <p>接下来，我们先实现默认配置</p> <p><code>defaults.ts</code>：</p> <div class="language-typescript line-numbers-mode"><pre class="language-typescript"><code><span class="token keyword">import</span> <span class="token punctuation">{</span> AxiosRequestConfig <span class="token punctuation">}</span> <span class="token keyword">from</span> <span class="token string">'./types'</span>

<span class="token keyword">const</span> defaults<span class="token operator">:</span> AxiosRequestConfig <span class="token operator">=</span> <span class="token punctuation">{</span>
  method<span class="token operator">:</span> <span class="token string">'get'</span><span class="token punctuation">,</span>

  timeout<span class="token operator">:</span> <span class="token number">0</span><span class="token punctuation">,</span>

  headers<span class="token operator">:</span> <span class="token punctuation">{</span>
    common<span class="token operator">:</span> <span class="token punctuation">{</span>
      Accept<span class="token operator">:</span> <span class="token string">'application/json, text/plain, */*'</span>
    <span class="token punctuation">}</span>
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span>

<span class="token keyword">const</span> methodsNoData <span class="token operator">=</span> <span class="token punctuation">[</span><span class="token string">'delete'</span><span class="token punctuation">,</span> <span class="token string">'get'</span><span class="token punctuation">,</span> <span class="token string">'head'</span><span class="token punctuation">,</span> <span class="token string">'options'</span><span class="token punctuation">]</span>

methodsNoData<span class="token punctuation">.</span><span class="token function">forEach</span><span class="token punctuation">(</span>method <span class="token operator">=&gt;</span> <span class="token punctuation">{</span>
  defaults<span class="token punctuation">.</span>headers<span class="token punctuation">[</span>method<span class="token punctuation">]</span> <span class="token operator">=</span> <span class="token punctuation">{</span><span class="token punctuation">}</span>
<span class="token punctuation">}</span><span class="token punctuation">)</span>

<span class="token keyword">const</span> methodsWithData <span class="token operator">=</span> <span class="token punctuation">[</span><span class="token string">'post'</span><span class="token punctuation">,</span> <span class="token string">'put'</span><span class="token punctuation">,</span> <span class="token string">'patch'</span><span class="token punctuation">]</span>

methodsWithData<span class="token punctuation">.</span><span class="token function">forEach</span><span class="token punctuation">(</span>method <span class="token operator">=&gt;</span> <span class="token punctuation">{</span>
  defaults<span class="token punctuation">.</span>headers<span class="token punctuation">[</span>method<span class="token punctuation">]</span> <span class="token operator">=</span> <span class="token punctuation">{</span>
    <span class="token string-property property">'Content-Type'</span><span class="token operator">:</span> <span class="token string">'application/x-www-form-urlencoded'</span>
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span><span class="token punctuation">)</span>

<span class="token keyword">export</span> <span class="token keyword">default</span> defaults
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br><span class="line-number">28</span><br><span class="line-number">29</span><br></div></div><p>我们定义了 <code>defaults</code> 常量，它包含默认请求的方法、超时时间，以及 <code>headers</code> 配置。</p> <p>未来我们会根据新的需求添加更多的默认配置。</p> <h3 id="添加到-axios-对象中"><a href="#添加到-axios-对象中" class="header-anchor">#</a> 添加到 axios 对象中</h3> <p>根据需求，我们要给 <code>axios</code> 对象添加一个 <code>defaults</code> 属性，表示默认配置：</p> <div class="language-typescript line-numbers-mode"><pre class="language-typescript"><code><span class="token keyword">export</span> <span class="token keyword">default</span> <span class="token keyword">class</span> <span class="token class-name">Axios</span> <span class="token punctuation">{</span>
  defaults<span class="token operator">:</span> AxiosRequestConfig
  interceptors<span class="token operator">:</span> Interceptors

  <span class="token function">constructor</span><span class="token punctuation">(</span>initConfig<span class="token operator">:</span> AxiosRequestConfig<span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token keyword">this</span><span class="token punctuation">.</span>defaults <span class="token operator">=</span> initConfig
    <span class="token keyword">this</span><span class="token punctuation">.</span>interceptors <span class="token operator">=</span> <span class="token punctuation">{</span>
      request<span class="token operator">:</span> <span class="token keyword">new</span> <span class="token class-name">InterceptorManager<span class="token operator">&lt;</span>AxiosRequestConfig<span class="token operator">&gt;</span></span><span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">,</span>
      response<span class="token operator">:</span> <span class="token keyword">new</span> <span class="token class-name">InterceptorManager<span class="token operator">&lt;</span>AxiosResponse<span class="token operator">&gt;</span></span><span class="token punctuation">(</span><span class="token punctuation">)</span>
    <span class="token punctuation">}</span>
  <span class="token punctuation">}</span>
  <span class="token comment">// ...</span>
<span class="token punctuation">}</span>  
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br></div></div><p>我们给 <code>Axios</code> 类添加一个 <code>defaults</code> 成员属性，并且让 <code>Axios</code> 的构造函数接受一个 <code>initConfig</code> 对象，把 <code>initConfig</code> 赋值给 <code>this.defaults</code>。</p> <p>接着修改 <code>createInstance</code> 方法，支持传入 <code>config</code> 对象。</p> <div class="language-typescript line-numbers-mode"><pre class="language-typescript"><code><span class="token keyword">import</span> defaults <span class="token keyword">from</span> <span class="token string">'./defaults'</span>

<span class="token keyword">function</span> <span class="token function">createInstance</span><span class="token punctuation">(</span>config<span class="token operator">:</span> AxiosRequestConfig<span class="token punctuation">)</span><span class="token operator">:</span> AxiosStatic <span class="token punctuation">{</span>
  <span class="token keyword">const</span> context <span class="token operator">=</span> <span class="token keyword">new</span> <span class="token class-name">Axios</span><span class="token punctuation">(</span>config<span class="token punctuation">)</span>
  <span class="token keyword">const</span> instance <span class="token operator">=</span> Axios<span class="token punctuation">.</span>prototype<span class="token punctuation">.</span><span class="token function">request</span><span class="token punctuation">.</span><span class="token function">bind</span><span class="token punctuation">(</span>context<span class="token punctuation">)</span>

  <span class="token comment">// extend(instance, Axios.prototype, context)</span>

  <span class="token function">extend</span><span class="token punctuation">(</span>instance<span class="token punctuation">,</span> context<span class="token punctuation">)</span>

  <span class="token keyword">return</span> instance <span class="token keyword">as</span> AxiosStatic
<span class="token punctuation">}</span>

<span class="token keyword">const</span> axios <span class="token operator">=</span> <span class="token function">createInstance</span><span class="token punctuation">(</span>defaults<span class="token punctuation">)</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br></div></div><p>这样我们就可以在执行 <code>createInstance</code> 创建 <code>axios</code> 对象的时候，把默认配置传入了。</p> <h2 id="配置合并及策略"><a href="#配置合并及策略" class="header-anchor">#</a> 配置合并及策略</h2> <p>定义了默认配置后，我们发送每个请求的时候需要把自定义配置和默认配置做合并，它并不是简单的 2 个普通对象的合并，对于不同的字段合并，会有不同的合并策略。举个例子：</p> <div class="language-typescript line-numbers-mode"><pre class="language-typescript"><code>config1 <span class="token operator">=</span> <span class="token punctuation">{</span>
  method<span class="token operator">:</span> <span class="token string">'get'</span><span class="token punctuation">,</span>

  timeout<span class="token operator">:</span> <span class="token number">0</span><span class="token punctuation">,</span>

  headers<span class="token operator">:</span> <span class="token punctuation">{</span>
    common<span class="token operator">:</span> <span class="token punctuation">{</span>
      Accept<span class="token operator">:</span> <span class="token string">'application/json, text/plain, */*'</span>
    <span class="token punctuation">}</span>
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span>

config2 <span class="token operator">=</span> <span class="token punctuation">{</span>
  url<span class="token operator">:</span> <span class="token string">'/config/post'</span><span class="token punctuation">,</span>
  method<span class="token operator">:</span> <span class="token string">'post'</span><span class="token punctuation">,</span>
  data<span class="token operator">:</span> <span class="token punctuation">{</span>
    a<span class="token operator">:</span> <span class="token number">1</span>
  <span class="token punctuation">}</span><span class="token punctuation">,</span>
  headers<span class="token operator">:</span> <span class="token punctuation">{</span>
    test<span class="token operator">:</span> <span class="token string">'321'</span>
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span>

merged <span class="token operator">=</span> <span class="token punctuation">{</span>
  url<span class="token operator">:</span> <span class="token string">'/config/post'</span><span class="token punctuation">,</span>
  method<span class="token operator">:</span> <span class="token string">'post'</span><span class="token punctuation">,</span>
  data<span class="token operator">:</span> <span class="token punctuation">{</span>
    a<span class="token operator">:</span> <span class="token number">1</span>
  <span class="token punctuation">}</span><span class="token punctuation">,</span>
  timeout<span class="token operator">:</span> <span class="token number">0</span><span class="token punctuation">,</span>
  headers<span class="token operator">:</span> <span class="token punctuation">{</span>
    common<span class="token operator">:</span> <span class="token punctuation">{</span>
      Accept<span class="token operator">:</span> <span class="token string">'application/json, text/plain, */*'</span>
    <span class="token punctuation">}</span>
    test<span class="token operator">:</span> <span class="token string">'321'</span>
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br><span class="line-number">28</span><br><span class="line-number">29</span><br><span class="line-number">30</span><br><span class="line-number">31</span><br><span class="line-number">32</span><br><span class="line-number">33</span><br><span class="line-number">34</span><br><span class="line-number">35</span><br><span class="line-number">36</span><br><span class="line-number">37</span><br></div></div><p>我们在 <code>core/mergeConfig.ts</code> 中实现合并方法。</p> <h3 id="合并方法"><a href="#合并方法" class="header-anchor">#</a> 合并方法</h3> <div class="language-typescript line-numbers-mode"><pre class="language-typescript"><code><span class="token keyword">export</span> <span class="token keyword">default</span> <span class="token keyword">function</span> <span class="token function">mergeConfig</span><span class="token punctuation">(</span>
  config1<span class="token operator">:</span> AxiosRequestConfig<span class="token punctuation">,</span>
  config2<span class="token operator">?</span><span class="token operator">:</span> AxiosRequestConfig
<span class="token punctuation">)</span><span class="token operator">:</span> AxiosRequestConfig <span class="token punctuation">{</span>
  <span class="token keyword">if</span> <span class="token punctuation">(</span><span class="token operator">!</span>config2<span class="token punctuation">)</span> <span class="token punctuation">{</span>
    config2 <span class="token operator">=</span> <span class="token punctuation">{</span><span class="token punctuation">}</span>
  <span class="token punctuation">}</span>

  <span class="token keyword">const</span> config <span class="token operator">=</span> Object<span class="token punctuation">.</span><span class="token function">create</span><span class="token punctuation">(</span><span class="token keyword">null</span><span class="token punctuation">)</span>

  <span class="token keyword">for</span> <span class="token punctuation">(</span><span class="token keyword">let</span> key <span class="token keyword">in</span> config2<span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token function">mergeField</span><span class="token punctuation">(</span>key<span class="token punctuation">)</span>
  <span class="token punctuation">}</span>

  <span class="token keyword">for</span> <span class="token punctuation">(</span><span class="token keyword">let</span> key <span class="token keyword">in</span> config1<span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token keyword">if</span> <span class="token punctuation">(</span><span class="token operator">!</span>config2<span class="token punctuation">[</span>key<span class="token punctuation">]</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
      <span class="token function">mergeField</span><span class="token punctuation">(</span>key<span class="token punctuation">)</span>
    <span class="token punctuation">}</span>
  <span class="token punctuation">}</span>

  <span class="token keyword">function</span> <span class="token function">mergeField</span><span class="token punctuation">(</span>key<span class="token operator">:</span> <span class="token builtin">string</span><span class="token punctuation">)</span><span class="token operator">:</span> <span class="token keyword">void</span> <span class="token punctuation">{</span>
    <span class="token keyword">const</span> strat <span class="token operator">=</span> strats<span class="token punctuation">[</span>key<span class="token punctuation">]</span> <span class="token operator">||</span> defaultStrat
    config<span class="token punctuation">[</span>key<span class="token punctuation">]</span> <span class="token operator">=</span> <span class="token function">strat</span><span class="token punctuation">(</span>config1<span class="token punctuation">[</span>key<span class="token punctuation">]</span><span class="token punctuation">,</span> config2<span class="token operator">!</span><span class="token punctuation">[</span>key<span class="token punctuation">]</span><span class="token punctuation">)</span>
  <span class="token punctuation">}</span>

  <span class="token keyword">return</span> config
<span class="token punctuation">}</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br></div></div><p>合并方法的整体思路就是对 <code>config1</code> 和 <code>config2</code> 中的属性遍历，执行 <code>mergeField</code> 方法做合并，这里 <code>config1</code> 代表默认配置，<code>config2</code> 代表自定义配置。</p> <p>遍历过程中，我们会通过 <code>config2[key]</code> 这种索引的方式访问，所以需要给 <code>AxiosRequestConfig</code> 的接口定义添加一个字符串索引签名：</p> <div class="language-typescript line-numbers-mode"><pre class="language-typescript"><code><span class="token keyword">export</span> <span class="token keyword">interface</span> <span class="token class-name">AxiosRequestConfig</span> <span class="token punctuation">{</span>
  <span class="token comment">// ...</span>

  <span class="token punctuation">[</span>propName<span class="token operator">:</span> <span class="token builtin">string</span><span class="token punctuation">]</span><span class="token operator">:</span> <span class="token builtin">any</span>
<span class="token punctuation">}</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br></div></div><p>在 <code>mergeField</code> 方法中，我们会针对不同的属性使用不同的合并策略。</p> <h3 id="默认合并策略"><a href="#默认合并策略" class="header-anchor">#</a> 默认合并策略</h3> <p>这是大部分属性的合并策略，如下：</p> <div class="language-typescript line-numbers-mode"><pre class="language-typescript"><code><span class="token keyword">function</span> <span class="token function">defaultStrat</span><span class="token punctuation">(</span>val1<span class="token operator">:</span> <span class="token builtin">any</span><span class="token punctuation">,</span> val2<span class="token operator">:</span> <span class="token builtin">any</span><span class="token punctuation">)</span><span class="token operator">:</span> <span class="token builtin">any</span> <span class="token punctuation">{</span>
  <span class="token keyword">return</span> <span class="token keyword">typeof</span> val2 <span class="token operator">!==</span> <span class="token string">'undefined'</span> <span class="token operator">?</span> val2 <span class="token operator">:</span> val1
<span class="token punctuation">}</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br></div></div><p>它很简单，如果有 <code>val2</code> 则返回 <code>val2</code>，否则返回 <code>val1</code>，也就是如果自定义配置中定义了某个属性，就采用自定义的，否则就用默认配置。</p> <h3 id="只接受自定义配置合并策略"><a href="#只接受自定义配置合并策略" class="header-anchor">#</a> 只接受自定义配置合并策略</h3> <p>对于一些属性如 <code>url</code>、<code>params</code>、<code>data</code>，合并策略如下：</p> <div class="language-typescript line-numbers-mode"><pre class="language-typescript"><code><span class="token keyword">function</span> <span class="token function">fromVal2Strat</span><span class="token punctuation">(</span>val1<span class="token operator">:</span> <span class="token builtin">any</span><span class="token punctuation">,</span> val2<span class="token operator">:</span> <span class="token builtin">any</span><span class="token punctuation">)</span><span class="token operator">:</span> <span class="token builtin">any</span> <span class="token punctuation">{</span>
  <span class="token keyword">if</span> <span class="token punctuation">(</span><span class="token keyword">typeof</span> val2 <span class="token operator">!==</span> <span class="token string">'undefined'</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token keyword">return</span> val2
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span>

<span class="token keyword">const</span> stratKeysFromVal2 <span class="token operator">=</span> <span class="token punctuation">[</span><span class="token string">'url'</span><span class="token punctuation">,</span> <span class="token string">'params'</span><span class="token punctuation">,</span> <span class="token string">'data'</span><span class="token punctuation">]</span>

stratKeysFromVal2<span class="token punctuation">.</span><span class="token function">forEach</span><span class="token punctuation">(</span>key <span class="token operator">=&gt;</span> <span class="token punctuation">{</span>
  strats<span class="token punctuation">[</span>key<span class="token punctuation">]</span> <span class="token operator">=</span> fromVal2Strat
<span class="token punctuation">}</span><span class="token punctuation">)</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br></div></div><p>因为对于 <code>url</code>、<code>params</code>、<code>data</code> 这些属性，默认配置显然是没有意义的，它们是和每个请求强相关的，所以我们只从自定义配置中获取。</p> <h3 id="复杂对象合并策略"><a href="#复杂对象合并策略" class="header-anchor">#</a> 复杂对象合并策略</h3> <p>对于一些属性如 <code>headers</code>，合并策略如下：</p> <div class="language-typescript line-numbers-mode"><pre class="language-typescript"><code><span class="token keyword">function</span> <span class="token function">deepMergeStrat</span><span class="token punctuation">(</span>val1<span class="token operator">:</span> <span class="token builtin">any</span><span class="token punctuation">,</span> val2<span class="token operator">:</span> <span class="token builtin">any</span><span class="token punctuation">)</span><span class="token operator">:</span> <span class="token builtin">any</span> <span class="token punctuation">{</span>
  <span class="token keyword">if</span> <span class="token punctuation">(</span><span class="token function">isPlainObject</span><span class="token punctuation">(</span>val2<span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token keyword">return</span> <span class="token function">deepMerge</span><span class="token punctuation">(</span>val1<span class="token punctuation">,</span> val2<span class="token punctuation">)</span>
  <span class="token punctuation">}</span> <span class="token keyword">else</span> <span class="token keyword">if</span> <span class="token punctuation">(</span><span class="token keyword">typeof</span> val2 <span class="token operator">!==</span> <span class="token string">'undefined'</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token keyword">return</span> val2
  <span class="token punctuation">}</span> <span class="token keyword">else</span> <span class="token keyword">if</span> <span class="token punctuation">(</span><span class="token function">isPlainObject</span><span class="token punctuation">(</span>val1<span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token keyword">return</span> <span class="token function">deepMerge</span><span class="token punctuation">(</span>val1<span class="token punctuation">)</span>
  <span class="token punctuation">}</span> <span class="token keyword">else</span> <span class="token keyword">if</span> <span class="token punctuation">(</span><span class="token keyword">typeof</span> val1 <span class="token operator">!==</span> <span class="token string">'undefined'</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token keyword">return</span> val1
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span>

<span class="token keyword">const</span> stratKeysDeepMerge <span class="token operator">=</span> <span class="token punctuation">[</span><span class="token string">'headers'</span><span class="token punctuation">]</span>

stratKeysDeepMerge<span class="token punctuation">.</span><span class="token function">forEach</span><span class="token punctuation">(</span>key <span class="token operator">=&gt;</span> <span class="token punctuation">{</span>
  strats<span class="token punctuation">[</span>key<span class="token punctuation">]</span> <span class="token operator">=</span> deepMergeStrat
<span class="token punctuation">}</span><span class="token punctuation">)</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br></div></div><p><code>helpers/util.ts</code>：</p> <div class="language-typescript line-numbers-mode"><pre class="language-typescript"><code><span class="token keyword">export</span> <span class="token keyword">function</span> <span class="token function">deepMerge</span><span class="token punctuation">(</span><span class="token operator">...</span>objs<span class="token operator">:</span> <span class="token builtin">any</span><span class="token punctuation">[</span><span class="token punctuation">]</span><span class="token punctuation">)</span><span class="token operator">:</span> <span class="token builtin">any</span> <span class="token punctuation">{</span>
  <span class="token keyword">const</span> result <span class="token operator">=</span> Object<span class="token punctuation">.</span><span class="token function">create</span><span class="token punctuation">(</span><span class="token keyword">null</span><span class="token punctuation">)</span>

  objs<span class="token punctuation">.</span><span class="token function">forEach</span><span class="token punctuation">(</span>obj <span class="token operator">=&gt;</span> <span class="token punctuation">{</span>
    <span class="token keyword">if</span> <span class="token punctuation">(</span>obj<span class="token punctuation">)</span> <span class="token punctuation">{</span>
      Object<span class="token punctuation">.</span><span class="token function">keys</span><span class="token punctuation">(</span>obj<span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">forEach</span><span class="token punctuation">(</span>key <span class="token operator">=&gt;</span> <span class="token punctuation">{</span>
        <span class="token keyword">const</span> val <span class="token operator">=</span> obj<span class="token punctuation">[</span>key<span class="token punctuation">]</span>
        <span class="token keyword">if</span> <span class="token punctuation">(</span><span class="token function">isPlainObject</span><span class="token punctuation">(</span>val<span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
          <span class="token keyword">if</span> <span class="token punctuation">(</span><span class="token function">isPlainObject</span><span class="token punctuation">(</span>result<span class="token punctuation">[</span>key<span class="token punctuation">]</span><span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token punctuation">{</span>
            result<span class="token punctuation">[</span>key<span class="token punctuation">]</span> <span class="token operator">=</span> <span class="token function">deepMerge</span><span class="token punctuation">(</span>result<span class="token punctuation">[</span>key<span class="token punctuation">]</span><span class="token punctuation">,</span> val<span class="token punctuation">)</span>
          <span class="token punctuation">}</span> <span class="token keyword">else</span> <span class="token punctuation">{</span>
            result<span class="token punctuation">[</span>key<span class="token punctuation">]</span> <span class="token operator">=</span> <span class="token function">deepMerge</span><span class="token punctuation">(</span><span class="token punctuation">{</span><span class="token punctuation">}</span><span class="token punctuation">,</span> val<span class="token punctuation">)</span>
          <span class="token punctuation">}</span>
        <span class="token punctuation">}</span> <span class="token keyword">else</span> <span class="token punctuation">{</span>
          result<span class="token punctuation">[</span>key<span class="token punctuation">]</span> <span class="token operator">=</span> val
        <span class="token punctuation">}</span>
      <span class="token punctuation">}</span><span class="token punctuation">)</span>
    <span class="token punctuation">}</span>
  <span class="token punctuation">}</span><span class="token punctuation">)</span>

  <span class="token keyword">return</span> result
<span class="token punctuation">}</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br></div></div><p>对于 <code>headers</code> 这类的复杂对象属性，我们需要使用深拷贝的方式，同时也处理了其它一些情况，因为它们也可能是一个非对象的普通值。未来我们讲到认证授权的时候，<code>auth</code> 属性也是这个合并策略。</p> <p>最后我们在 <code>request</code> 方法里添加合并配置的逻辑：</p> <div class="language-typescript line-numbers-mode"><pre class="language-typescript"><code>config <span class="token operator">=</span> <span class="token function">mergeConfig</span><span class="token punctuation">(</span><span class="token keyword">this</span><span class="token punctuation">.</span>defaults<span class="token punctuation">,</span> config<span class="token punctuation">)</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br></div></div><h2 id="flatten-headers"><a href="#flatten-headers" class="header-anchor">#</a> flatten headers</h2> <p>经过合并后的配置中的 <code>headers</code> 是一个复杂对象，多了 <code>common</code>、<code>post</code>、<code>get</code> 等属性，而这些属性中的值才是我们要真正添加到请求 <code>header</code> 中的。</p> <p>举个例子：</p> <div class="language-typescript line-numbers-mode"><pre class="language-typescript"><code>headers<span class="token operator">:</span> <span class="token punctuation">{</span>
  common<span class="token operator">:</span> <span class="token punctuation">{</span>
    Accept<span class="token operator">:</span> <span class="token string">'application/json, text/plain, */*'</span>
  <span class="token punctuation">}</span><span class="token punctuation">,</span>
  post<span class="token operator">:</span> <span class="token punctuation">{</span>
    <span class="token string-property property">'Content-Type'</span><span class="token operator">:</span><span class="token string">'application/x-www-form-urlencoded'</span>
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br></div></div><p>我们需要把它压成一级的，如下：</p> <div class="language-typescript line-numbers-mode"><pre class="language-typescript"><code>headers<span class="token operator">:</span> <span class="token punctuation">{</span>
  Accept<span class="token operator">:</span> <span class="token string">'application/json, text/plain, */*'</span><span class="token punctuation">,</span>
 <span class="token string-property property">'Content-Type'</span><span class="token operator">:</span><span class="token string">'application/x-www-form-urlencoded'</span>
<span class="token punctuation">}</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br></div></div><p>这里要注意的是，对于 <code>common</code> 中定义的 <code>header</code> 字段，我们都要提取，而对于 <code>post</code>、<code>get</code> 这类提取，需要和该次请求的方法对应。</p> <p>接下来我们实现 <code>flattenHeaders</code> 方法。</p> <p><code>helpers/header.ts</code>：</p> <div class="language-typescript line-numbers-mode"><pre class="language-typescript"><code><span class="token keyword">export</span> <span class="token keyword">function</span> <span class="token function">flattenHeaders</span><span class="token punctuation">(</span>headers<span class="token operator">:</span> <span class="token builtin">any</span><span class="token punctuation">,</span> method<span class="token operator">:</span> Method<span class="token punctuation">)</span><span class="token operator">:</span> <span class="token builtin">any</span> <span class="token punctuation">{</span>
  <span class="token keyword">if</span> <span class="token punctuation">(</span><span class="token operator">!</span>headers<span class="token punctuation">)</span> <span class="token punctuation">{</span>
    <span class="token keyword">return</span> headers
  <span class="token punctuation">}</span>
  headers <span class="token operator">=</span> <span class="token function">deepMerge</span><span class="token punctuation">(</span>headers<span class="token punctuation">.</span>common <span class="token operator">||</span> <span class="token punctuation">{</span><span class="token punctuation">}</span><span class="token punctuation">,</span> headers<span class="token punctuation">[</span>method<span class="token punctuation">]</span> <span class="token operator">||</span> <span class="token punctuation">{</span><span class="token punctuation">}</span><span class="token punctuation">,</span> headers<span class="token punctuation">)</span>

  <span class="token keyword">const</span> methodsToDelete <span class="token operator">=</span> <span class="token punctuation">[</span><span class="token string">'delete'</span><span class="token punctuation">,</span> <span class="token string">'get'</span><span class="token punctuation">,</span> <span class="token string">'head'</span><span class="token punctuation">,</span> <span class="token string">'options'</span><span class="token punctuation">,</span> <span class="token string">'post'</span><span class="token punctuation">,</span> <span class="token string">'put'</span><span class="token punctuation">,</span> <span class="token string">'patch'</span><span class="token punctuation">,</span> <span class="token string">'common'</span><span class="token punctuation">]</span>

  methodsToDelete<span class="token punctuation">.</span><span class="token function">forEach</span><span class="token punctuation">(</span>method <span class="token operator">=&gt;</span> <span class="token punctuation">{</span>
    <span class="token keyword">delete</span> headers<span class="token punctuation">[</span>method<span class="token punctuation">]</span>
  <span class="token punctuation">}</span><span class="token punctuation">)</span>

  <span class="token keyword">return</span> headers
<span class="token punctuation">}</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br></div></div><p>我们可以通过 <code>deepMerge</code> 的方式把 <code>common</code>、<code>post</code> 的属性拷贝到 <code>headers</code> 这一级，然后再把 <code>common</code>、<code>post</code> 这些属性删掉。</p> <p>然后我们在真正发送请求前执行这个逻辑。</p> <p><code>core/dispatchRequest.ts</code>：</p> <div class="language-typescript line-numbers-mode"><pre class="language-typescript"><code><span class="token keyword">function</span> <span class="token function">processConfig</span><span class="token punctuation">(</span>config<span class="token operator">:</span> AxiosRequestConfig<span class="token punctuation">)</span><span class="token operator">:</span> <span class="token keyword">void</span> <span class="token punctuation">{</span>
  config<span class="token punctuation">.</span>url <span class="token operator">=</span> <span class="token function">transformURL</span><span class="token punctuation">(</span>config<span class="token punctuation">)</span>
  config<span class="token punctuation">.</span>headers <span class="token operator">=</span> <span class="token function">transformHeaders</span><span class="token punctuation">(</span>config<span class="token punctuation">)</span>
  config<span class="token punctuation">.</span>data <span class="token operator">=</span> <span class="token function">transformRequestData</span><span class="token punctuation">(</span>config<span class="token punctuation">)</span>
  config<span class="token punctuation">.</span>headers <span class="token operator">=</span> <span class="token function">flattenHeaders</span><span class="token punctuation">(</span>config<span class="token punctuation">.</span>headers<span class="token punctuation">,</span> config<span class="token punctuation">.</span>method<span class="token operator">!</span><span class="token punctuation">)</span>
<span class="token punctuation">}</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br></div></div><p>这样确保我们了配置中的 <code>headers</code> 是可以正确添加到请求 <code>header</code> 中的</p> <h2 id="demo-编写"><a href="#demo-编写" class="header-anchor">#</a> demo 编写</h2> <p>在 <code>examples</code> 目录下创建 <code>config</code> 目录，在 <code>config</code> 目录下创建 <code>index.html</code>:</p> <div class="language-html line-numbers-mode"><pre class="language-html"><code><span class="token doctype"><span class="token punctuation">&lt;!</span><span class="token doctype-tag">DOCTYPE</span> <span class="token name">html</span><span class="token punctuation">&gt;</span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>html</span> <span class="token attr-name">lang</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">&quot;</span>en<span class="token punctuation">&quot;</span></span><span class="token punctuation">&gt;</span></span>
  <span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>head</span><span class="token punctuation">&gt;</span></span>
    <span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>meta</span> <span class="token attr-name">charset</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">&quot;</span>utf-8<span class="token punctuation">&quot;</span></span><span class="token punctuation">&gt;</span></span>
    <span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>title</span><span class="token punctuation">&gt;</span></span>Config example<span class="token tag"><span class="token tag"><span class="token punctuation">&lt;/</span>title</span><span class="token punctuation">&gt;</span></span>
  <span class="token tag"><span class="token tag"><span class="token punctuation">&lt;/</span>head</span><span class="token punctuation">&gt;</span></span>
  <span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>body</span><span class="token punctuation">&gt;</span></span>
    <span class="token tag"><span class="token tag"><span class="token punctuation">&lt;</span>script</span> <span class="token attr-name">src</span><span class="token attr-value"><span class="token punctuation attr-equals">=</span><span class="token punctuation">&quot;</span>/__build__/config.js<span class="token punctuation">&quot;</span></span><span class="token punctuation">&gt;</span></span><span class="token script"></span><span class="token tag"><span class="token tag"><span class="token punctuation">&lt;/</span>script</span><span class="token punctuation">&gt;</span></span>
  <span class="token tag"><span class="token tag"><span class="token punctuation">&lt;/</span>body</span><span class="token punctuation">&gt;</span></span>
<span class="token tag"><span class="token tag"><span class="token punctuation">&lt;/</span>html</span><span class="token punctuation">&gt;</span></span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br></div></div><p>接着创建 <code>app.ts</code> 作为入口文件：</p> <div class="language-typescript line-numbers-mode"><pre class="language-typescript"><code><span class="token keyword">import</span> axios <span class="token keyword">from</span> <span class="token string">'../../src/index'</span>
<span class="token keyword">import</span> qs <span class="token keyword">from</span> <span class="token string">'qs'</span>

axios<span class="token punctuation">.</span>defaults<span class="token punctuation">.</span>headers<span class="token punctuation">.</span>common<span class="token punctuation">[</span><span class="token string">'test2'</span><span class="token punctuation">]</span> <span class="token operator">=</span> <span class="token number">123</span>

<span class="token function">axios</span><span class="token punctuation">(</span><span class="token punctuation">{</span>
  url<span class="token operator">:</span> <span class="token string">'/config/post'</span><span class="token punctuation">,</span>
  method<span class="token operator">:</span> <span class="token string">'post'</span><span class="token punctuation">,</span>
  data<span class="token operator">:</span> qs<span class="token punctuation">.</span><span class="token function">stringify</span><span class="token punctuation">(</span><span class="token punctuation">{</span>
    a<span class="token operator">:</span> <span class="token number">1</span>
  <span class="token punctuation">}</span><span class="token punctuation">)</span><span class="token punctuation">,</span>
  headers<span class="token operator">:</span> <span class="token punctuation">{</span>
    test<span class="token operator">:</span> <span class="token string">'321'</span>
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span><span class="token punctuation">)</span><span class="token punctuation">.</span><span class="token function">then</span><span class="token punctuation">(</span><span class="token punctuation">(</span>res<span class="token punctuation">)</span> <span class="token operator">=&gt;</span> <span class="token punctuation">{</span>
  <span class="token builtin">console</span><span class="token punctuation">.</span><span class="token function">log</span><span class="token punctuation">(</span>res<span class="token punctuation">.</span>data<span class="token punctuation">)</span>
<span class="token punctuation">}</span><span class="token punctuation">)</span>
</code></pre> <div class="line-numbers-wrapper"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br></div></div><p>这个例子中我们额外引入了 <code>qs</code> 库，它是一个查询字符串解析和字符串化的库。</p> <p>比如我们的例子中对于 <code>{a:1}</code> 经过 <code>qs.stringify</code> 变成 <code>a=1</code>。</p> <p>由于我们的例子给默认值添加了 <code>post</code> 和 <code>common</code> 的 <code>headers</code>，我们在请求前做配置合并，于是我们请求的 <code>header</code> 就添加了 <code>Content-Type</code> 字段，它的值是 <code>application/x-www-form-urlencoded</code>；另外我们也添加了 <code>test2</code> 字段，它的值是 <code>123</code>。</p> <p>至此，我们合并配置的逻辑就实现完了。我们在前面的章节编写 <code>axios</code> 的基础功能的时候对请求数据和响应数据都做了处理，官方 <code>axios</code> 则把这俩部分逻辑也做到了默认配置中，意味这用户可以去修改这俩部分的逻辑，实现自己对请求和响应数据处理的逻辑。那么下一节我们就来实现这个 feature。</p></div></div> <!----> <div class="page-edit"><div class="edit-link"><a href="https://github.com/xugaoyi/vuepress-theme-vdoing/edit/master/docs/《TypeScript 从零实现 axios》/08.ts-axios 配置化实现/01.合并配置的设计与实现.md" target="_blank" rel="noopener noreferrer">编辑</a> <span><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" x="0px" y="0px" viewBox="0 0 100 100" width="15" height="15" class="icon outbound"><path fill="currentColor" d="M18.8,85.1h56l0,0c2.2,0,4-1.8,4-4v-32h-8v28h-48v-48h28v-8h-32l0,0c-2.2,0-4,1.8-4,4v56C14.8,83.3,16.6,85.1,18.8,85.1z"></path> <polygon fill="currentColor" points="45.7,48.7 51.3,54.3 77.2,28.5 77.2,37.2 85.2,37.2 85.2,14.9 62.8,14.9 62.8,22.9 71.5,22.9"></polygon></svg> <span class="sr-only">(opens new window)</span></span></div> <!----> <!----></div> <div class="page-nav-wapper"><div class="page-nav-centre-wrap"><a href="/vdoing-demo-repository/pages/70651900f022f586/" class="page-nav-centre page-nav-centre-prev"><div class="tooltip">拦截器设计与实现</div></a> <a href="/vdoing-demo-repository/pages/f5b627bfebba87fc/" class="page-nav-centre page-nav-centre-next"><div class="tooltip">请求和响应配置化</div></a></div> <div class="page-nav"><p class="inner"><span class="prev">
        ←
        <a href="/vdoing-demo-repository/pages/70651900f022f586/" class="prev">拦截器设计与实现</a></span> <span class="next"><a href="/vdoing-demo-repository/pages/f5b627bfebba87fc/">请求和响应配置化</a>→
      </span></p></div></div></div> <!----></main></div> <div class="footer"><!----> 
  Theme by
  <a href="https://github.com/xugaoyi/vuepress-theme-vdoing" target="_blank" title="本站主题">Vdoing</a> 
    | Copyright © 2019-2023
    <span>Evan Xu | MIT License</span></div> <div class="buttons"><div title="返回顶部" class="button blur go-to-top iconfont icon-fanhuidingbu" style="display:none;"></div> <div title="去评论" class="button blur go-to-comment iconfont icon-pinglun" style="display:none;"></div> <div title="主题模式" class="button blur theme-mode-but iconfont icon-zhuti"><ul class="select-box" style="display:none;"><li class="iconfont icon-zidong">
          跟随系统
        </li><li class="iconfont icon-rijianmoshi">
          浅色模式
        </li><li class="iconfont icon-yejianmoshi">
          深色模式
        </li><li class="iconfont icon-yuedu">
          阅读模式
        </li></ul></div></div> <!----> <!----> <!----></div><div class="global-ui"></div></div>
    <script src="/vdoing-demo-repository/assets/js/app.52e6b5d0.js" defer></script><script src="/vdoing-demo-repository/assets/js/2.f10ddeba.js" defer></script><script src="/vdoing-demo-repository/assets/js/152.ca32ca39.js" defer></script>
  </body>
</html>
